Which of the following statements about the muscular system is correct?
1
Skeletal muscles are responsible for involuntary movements such as heart contractions and digestion
2
Smooth muscles are primarily found in the walls of hollow organs and are under voluntary control.
3
Cardiac muscle is striated like skeletal muscle but is unique in that its contractions are under involuntary control.
4
The primary function of the muscular system is to produce hormones and regulate body temperature.